The Surgery of the Skull and Brain

by Louis Bathe Rawling

Whatever the circumstances of the case, the preliminary details are identical. The scalp is shaved, cleansed, the head enveloped in gauze, and the scalp-tourniquet applied.

The formation of the scalp-flap.

When the scalp is adherent to the bone, the incision, carried throughout down to the bone, is made in such a manner that the flap will not only allow of the detachment of the scar, but will also permit of the complete exposure of the neighbouring portion of the skull.

When the scalp is adherent to dura or brain, as the result of osseous deficiency, the edge of the knife should be directed towards the under aspect of the flap, and the flap carefully peeled away from the region of the gap.

The examination of the bone.

When no fracture is found, the operator should trephine over the cortical area from which the trouble appears to emanate.

When a fissured fracture is found, trephining is carried out where the line of fracture cuts across that region of the brain which appears to be involved.

When a depressed fracture is found, the trephine is applied in such a manner that the circle just includes the outer segment of the depression. After removal of the disk, the dura mater should be peeled away from the under surface of the bone, and the whole of the depressed area cut away with the craniectomy forceps.

When there is osseous deficiency and when the gap is filled in with fibrous tissue, adherent to the margins of the gap and probably to the dura or brain as well, it is essential that this fibrous tissue should be freely removed. All evidence goes to substantiate the statement that meningeal irritation is the main cause of the fits, &c.

The removal of this tissue is best carried out by beginning at the most promising part of the gap, detaching the tissue adherent to the most prominent portion of the bone, and exposing the underlying dura mater. The central mass of scar tissue should then be seized with forceps, lifted up and detached as completely as possible, both from the margins of the gap and from the underlying dura or brain. In the more complicated cases, where the scar tissue is adherent to dura and brain, the most careful dissection is required, and in many instances it is necessary to include that part of the dura mater which is incorporated with the scar. The cerebral substance should be carefully protected (see below).